The scenario you describe is not consistent with manual undo. Was the database created/started with automatic undo and you have switched to manual?

A.Bahar_at_billing-components.com wrote:
> > I use manual managed undo tablespace but there are some system named rollback segments on that> tablespace ( I did not created them ) and they can not be dropped.> What are they , how can I drop them.> --> Please see the official ORACLE-L FAQ: http://www.orafaq.net> --> Author: <A.Bahar_at_billing-components.com> INET: A.Bahar_at_billing-components.com> > Fat City Network Services -- 858-538-5051 http://www.fatcity.com> San Diego, California -- Mailing list and web hosting services> ---------------------------------------------------------------------> To REMOVE yourself from this mailing list, send an E-Mail message> to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in> the message BODY, include a line containing: UNSUB ORACLE-L> (or the name of mailing list you want to be removed from). You may> also send the HELP command for other information (like subscribing).

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Please see the official ORACLE-L FAQ: http://www.orafaq.net
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Author: <A.Bahar_at_billing-components.com
INET: A.Bahar_at_billing-components.com
Fat City Network Services -- 858-538-5051 http://www.fatcity.com
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